Mirka Ltd.

Mirka Oy

Tomas Södergård

Caj Nordström

Simon Bäck

Tobias Holmqvist

Stig Finnäs

Caj NORDSTRÖM

There is provided be a brushless direct current, BLDC, electric motor. The BLDC electric motor comprises a rotor comprising a rotor shaft and a stator arranged around the rotor shaft. The stator comprises a stator hub comprising electromagnets, and cooling channels extending in a direction that is parallel to a longitudinal direction of the rotor shaft and the cooling channels are positioned between the rotor shaft and the electromagnets.

Brushless direct current electric motor and handheld tool

There is provided a solution for electrical insulation for an output shaft, tool and/or accessory driven by an electric motor, and the presence of the electrical insulation is also easy to verify. A rotor shaft assembly for an electric motor includes at least one section that is configured to extend in an axial direction of the rotor shaft assembly outside of a stator assembly of the electric motor, when the rotor shaft assembly is rotatably mounted inside the stator assembly. An electrical insulator is connected to the at least one section and the electrical insulator is configured to connect to an output shaft for connecting with a tool and/or accessory, or configured to connect directly to a tool and/or accessory to be driven by the electric motor.

Rotor shaft assembly, method for manufacturing of rotor shaft assembly and devices comprising rotor shaft assembly

The application concerns a cooling arrangement for a power tool and a power tool comprising the cooling arrangement. According to an aspect of the invention a cooling arrangement for a power tool comprises a housing of the power tool and electronics. The electronics include at least one circuit board and at least one electronic component. The electronics comprise at least one heat conductive area. The at least one heat conductive area is arranged to be heat conductively connected to the housing of the power tool.

Cooling arrangement for a power tool and power tool electronics

A power tool with a direct current, DC, power source comprising a controller for controlling a driver circuit driving a brushless motor in a power tool, the driver circuit being coupled to a direct current, DC, power source and including a first switching element pair coupled to a first phase winding of the brushless motor and a second switching element pair coupled to a second phase winding of the brushless motor; and the controller being arranged to alternately switch a first switching element of the first switching element pair and a second switching element of the second switching element pair, wherein the first switching element and the second switching elements are coupled to a respective terminal of the DC power source. A power tool comprising such a controller, and a method of controlling a driver circuit driving a brushless motor in a power tool.

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Nykarleby, Finland

Tomas Södergård